Waste Water Recovery System

ABSTRACT

A waste water recovery system to filter and recirculate waste water to a wash system including a fluid recovery line, a fluid supply line and a fluid backwash line comprising a filter assembly including a water filtering section to receive waste water from the wash system and to recirculate filtered water to the wash system and a filter backwash section to selectively clean the water filtering section when a system condition exists, and a fluid control including a plurality of valve assemblies operatively coupled between the wash system, the water filtering section and the filter backwash section to selectively control the circulation of water through the water filtering section to recirculate the recovery water to the wash system and to periodically

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 11/060,112, filed Feb. 17, 2005 by James Keller, currently pending and hereby incorporated by reference in the entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

A waste water recovery system to filter and recirculate waste water from and to a wash system.

2. Description of the Prior Art

Numerous efforts have been made to design an efficient system to recover and recirculate waste water from car washes and other industrial processes. Such designs typically incorporate self-cleaning capabilities to periodically clean filtering devices common to these systems. In order to provide essentially continuous or uninterrupted operation of such wash systems, a secondary supply or source of water is needed during the filter cleaning phase.

Filter devices often include a filter element and an air purge using the fluid in the filter device to dislodge the particulate contaminants adhering to the surface of the filter element and to force the particulate contaminates from the filter device.

However, a need remains to construct a reliable means to provide a virtually uninterrupted flow of recovered water to the car wash or other industrial process.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and object of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a schematic diagram of the waste water recovery system of the present invention and a wash system.

FIG. 2 is a top view of the waste water recovery system of the present invention.

FIG. 3 is a detailed cross-sectional view of the waste water recovery system of the present invention.

FIG. 4 is a partial end view of the waste water recovery system of the present invention.

FIG. 5 depicts the position or state of the valve assemblies of the waste water recovery system of the present invention when in the full filter mode or configuration.

FIGS. 6 and 7 depict the position of state of the valve assemblies of the waste water recovery system of the present invention when one of the filters is in the backflush mode or configuration.

FIG. 8 depicts the position of state of the valve assemblies of the waste water recovery system of the present invention when the filter is in the purge mode or configuration.

FIG. 9 depicts the position of state of the valve assemblies of the waste water recovery system of the present invention when in the full filter mode or configuration after the first filter has completed the backwash cycle.

FIGS. 10 and 11 depict the position of state of the valve assemblies of the waste water recovery system of the present invention when the other filter is in the backwash mode or configuration.

FIG. 12 depicts the position of state of the valve assemblies of the waste water recovery system of the present invention when the second filter is in the purge mode or configuration.

FIG. 13 depicts the position of state of the valve assemblies of the waste water recovery system of the present invention when in the full flush mode or configuration after the second filter has completed the backwash cycle.

Similar reference characters refer to similar parts throughout the several views of the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in FIG. 1, the present invention relates to a waste water recovery system generally indicated as 10 to filter and recirculate waste water from a wash system generally indicated as 12 such as a car wash or other industrial process. The wash system 12 comprises a wash device generally indicated as 14 including a wash water applicator 16, a waste water recovery reservoir generally indicated as 18 including a plurality of recovery tanks each indicated as 20 and a drain sump 22. A fluid recovery outlet 24 of the waste water recovery reservoir 18 of the wash system 12 is coupled to a fluid recover inlet 26 of the waste water recovery system 10 by a fluid recovery line 28, a fluid supply outlet 30 of the waste water recovery system 10 is coupled to a fluid supply inlet 32 of the wash device 14 of the wash system 12 by a recovered water supply line 34 and a fluid backflush outlet 36 of the waste water recovery system 10 is coupled to a fluid backwash inlet 38 of the drain sump 22 of the wash system 12 by a fluid backwash line 40.

As shown in FIGS. 1 through 4, the waste water recovery system 10 comprises a filter assembly including a water filtering section generally indicated as 42 including a pair of filters each generally indicated as 44 and a pair of fluid circulating pumps each indicated as 46 coupled thereto by a pump outlet conduit arrangement generally indicated as 48 to continuously filter wash water from the wash system 12 when the wash system is operating and to recirculate the filtered water to the wash device 14 of the wash system 12. The waste water recovery system 10 further comprises a filter backwash or cleaning section including a pressurized purge air source 50 coupled to each filter 44 through a purge air inlet 52 by a pressurized purge air supply line 54 and to the fluid backwash line 40 through a fluid purge outlet 56 by a fluid purge line 58 exists to selectively clean each of the filters 44 when certain system condition as described more fully hereinafter. Disposed between the fluid recovery outlet 24 and the fluid recovery inlet 26 is a basket strainer 60 and a check valve assembly 62.

The waste water recovery system 10 also includes a fluid control comprising a plurality of valve assemblies operatively coupled between the wash system 12, the water filtering section 42 and the filter backwash or cleaning section to selectively control the circulation of water through each filter 44 to recirculate the recovery water to the wash system 12 and to periodically clean each filter 44 separately.

As shown in FIG. 2, the pump inlet 110 of each circulating pump 46 is coupled to the fluid recovery line 28 by the fluid recovery inlet 20 to receive wash water to be filtered by the filters 44 as described hereinafter. The pump outlet conduit arrangement 48 comprising a pump outlet conduit 112 coupled between a pump outlet 114 and a filter port 116 formed in the lower portion of the corresponding filter 44 and a cross-flow or interconnecting pump outlet conduit 118 coupled between the pump outlet conduits 112.

As shown in FIG. 3, each filter 44 comprises an outer housing or shell 120 and an upper cover 122 to cooperatively form a filter chamber 124 to operatively receive a filter element or member 125 therein to filter water entering the filter chamber 124 through the filter port 116 and a filter outlet 126 formed in the upper portion of the filter 44 coupled to the fluid supply line 34 by a corresponding filter outlet conduit 128 to selectively feed filtered recovery water to the wash system 12.

The waste water recovery system 10 further includes a fluid control including a plurality of valve assemblies operatively coupled between the wash system 12, the water filter section and the filter backwash or cleaning section and a control section 208 including control logic to control the position or state of each of the plurality of valve assemblies in accordance with a sequence of modes or configurations and duration of time or sensed pressure. Specifically, the plurality of valve assemblies comprises a first and second filter inlet valve assembly indicated as 210 and 212 respectively each coupled between one of the filter ports 116 and the pump outlets 114 through the pump outlet conduits 112 and 118 to selectively control the flow of waste water from the circulating pumps 46 to the corresponding filter(s) 44, a first and second filter outlet valve assembly indicated as 214 and 216 respectively each coupled between one of the filter outlets 126 and the recovered water supply line 34 to selectively control the flow of recovered water from the corresponding filter(s) 44 to the wash system 12, a first and second backwash/purge inlet valve assembly 218 and 220 respectively each coupled between the pressurized purge air source 50 to selectively control the flow of pressurized air into the air chamber 124 of the corresponding filter 44, a first and second backflush outlet valve assembly 222 and 224 respectively each coupled between one the filter ports 116 and the fluid backwash line 40 by a backwash conduit 225 to feed backwash to the drain sump 22 and a first and second purge outlet valve assembly 226 and 228 respectively each coupled to one of the purge air outlets 56 by one of the purge air conduits 58 to feed purge air to the drain sump 22.

The waste water recovery system 10 is selectively operable in a full filter mode where both filters 44 filter waste water, a dual mode where one of the filters 44 is filtering waste water and the other filter 44 is backwashed or cleaned while the wash system 10 is operating, and a backwash mode where one of the filters 44 is cleaned.

As shown in FIG. 5, when the wash system 12 is in use, and the waste water recovery system 10 is operating in a normal service cycle, the control logic of the control section causes the first filter inlet valve assembly 210 and the first filter outlet valve assembly 214 to be open permitting waste water feed from the corresponding pump 46 to flow through the filter port 116, the filter member or medium 125 and out the filter outlet 126. Similarly, the second filter inlet valve assembly 212 and the second filter outlet valve assembly 216 are open permitting waste water from the other pump 46 to flow through the filter member or medium 125 and out the filter outlet 126 of the other filter 44. The remaining valve assemblies 218, 222 and 226, and 220, 224 and 228 are in the closed position. So configured, the waste water recovery system 10 is operating in the full filter mode.

After a predetermined period of time, such as about 4 minutes, the control logic of the control section will cause one of the filters 44 to transition to the cleaning or backwash mode including a backflush stage and a purge stage. As shown in FIG. 6, the valve assembly 218 is opened and 210, 214, 222 and 226 of the filters 44 to be cleaned are closed, stopping the flow of water to the first filter 44 and to feed air from the pressurized air source 50 through the air inlet 132 to charge or pressurize the filter chamber 124. The position or state of the valve assemblies 212, 216, 220, 224 and 228 of the other or second filter 44 remains unchanged allowing water to continue to filter therethrough.

After the filter chamber 124 is charged for a predetermined period of time such as about 4 seconds with the valve assembly 218 remaining open, the first backflush outlet valve assembly 222 is opened for a predetermined period of time such as 4 seconds. The other valve assemblies 210, 214 and 226 remain closed, allowing water to be backflushed through the filter medium or member 125 through the filter port 116, and the fluid backwash line 40 to the drain sump 22 as shown in FIG. 7.

After a predetermined period of time, such as about 9 seconds, the valve assemblies 218 and 222 are closed as the valve assemblies 210 and 226 and opened. The valve assembly 214 remains closed as shown in FIG. 8. This allows water to flow from the pump assembly through the filter port 116 forcing the air from the filter chamber 125 through the purge outlet 136 purging the recovery tank 20 of air through the purge conduit 138 and the fluid backwash line 40 to the drain sump 22. The valve assembly 226 is closed and the valve assembly 214 is opened returning the waste water recovery system 10 to the full filter mode with both filters 44 filtering waste water as shown in FIG. 9. This backwash cycle of backflushing and purging the first filter 44 by controlling the valve assemblies 210, 214, 218, 222 and 226 may be completed once or twice.

After a predetermined period of time, such as about 10 seconds, the control logic starts the backwash cycle including the backflush and purge stages for the other filter s 44 similar to that of the first filter 44 as shown in FIGS. 10 through 12.

The control section will continue to cycle the filters 44 so long as the wash system 12 is operating. When the wash system 12 is not operating, the control section will automatically backwash the filters 44 from time to time.

The cross-flow or interconnecting pump outlet conduit 118 allows the pumps 46 to feed both filters 44 when in the full filtering mode and either filters 44 when the other filter is in the backwash mode to maintain a substantially constant volume of water filtering. 

1. A waste water recovery system for filtering waste water received from a fluid recovery line and returning filtered water to a fluid supply line, comprising: at least one filter assembly(s), each of the filter assembly(s) provided with a filter chamber containing a filter element dividing the filter chamber between a filter outlet side provided with a filter outlet and a filter port side provided with a filter port; a filter inlet valve assembly between the fluid recovery line and the filter port; a backwash outlet valve assembly between the filter port and a fluid backwash line; a filter outlet valve assembly between the filter port and the fluid supply line operable to open or close a fluid connection between the filter outlet and the fluid supply line; an air purge inlet on the filter outlet side; and an air purge outlet coupled to the filter outlet side.
 2. The waste water recovery system of claim 1, wherein the at least one filter assembly(s) is two filter assemblies.
 3. The waste water recovery system of claim 1, further including at least one pump between the fluid recovery line and the at least one filter assembly(s).
 4. The waste water recovery system of claim 1, wherein the air purge outlet is coupled to the fluid backwash line.
 5. The waste water recovery system of claim 1, further including a backwash/purge inlet valve assembly between a pressurized air source and the air purge inlet.
 6. The waste water recovery system of claim 5, further including a control section operable to control a position of the filter inlet assembly, the backwash outlet valve assembly, the filter outlet valve assembly and the backwash/purge inlet valve assembly of each of the filter assembly(s).
 7. The waste water recovery system of claim 6, wherein the waste recovery system is selectively operable via the control section in one of: a full filter mode wherein each of the filter assembly(s) filters waste water passing from the fluid recovery line to the fluid supply line; and a dual filter mode wherein at least one of the filter assembly(s) filters waste water passing from the fluid recovery line to the fluid supply line and at least one of the filter assembly(s) is in a backwash mode.
 8. The waste water recovery system of claim 5, wherein the control section sequences the position of the filter inlet assembly, the backwash outlet valve assembly, the filter outlet valve assembly and the backwash/purge inlet valve assembly of each of the filter assembly(s) according to a plurality of predetermined time(s).
 9. The waste water recovery system of claim 1, wherein the air purge inlet extends into the filter chamber.
 10. A waste water recovery system for filtering waste water received from a fluid recovery line and returning filtered water to a fluid supply line, comprising: two filter assembly(s), each of the filter assembly(s) provided with a filter chamber containing a filter element dividing the filter chamber between a filter outlet side provided with a filter outlet and a filter port side provided with a filter port; a filter inlet valve assembly between the fluid recovery line and the filter port; a backwash outlet valve assembly between the filter port and a fluid backwash line; a filter outlet valve assembly between the filter port and the fluid supply line operable to open or close a fluid connection between the filter outlet and the fluid supply line; an air purge inlet on the filter outlet side; a backwash/purge inlet valve assembly between a pressurized air source and the air purge inlet; and an air purge outlet located on the filter outlet side of the filter element; and at least one pump coupled between the fluid recovery line and a pump outlet conduit network, the pump outlet conduit network coupled to each filter assembly.
 11. The waste water recovery system of claim 10, further including a control section; the control section configurable with a plurality of time periods for sequencing operation of the waste water recovery system.
 12. A method for operating a waste water recovery system to filter and recirculate waste water to a wash system including a fluid recovery line, a fluid supply line and a fluid backwash line, comprising the steps of circulating water from the fluid recovery line through a plurality of filters to the fluid supply line during a full filter mode; upon a system condition initiating a backwash mode for at least one of the filters wherein the at least one filter(s) in backwash mode is isolated from the fluid recovery line and the fluid supply line and coupled to a pressurized air supply in a charge step; after a charge time coupling the at least one filter(s) in backwash mode to the fluid backwash line in a purge step; after a purge time, initiating an air purge step wherein the at least one filter(s) in backwash mode has an air purge outlet opened and the fluid recovery line opened to purge air from the at least one filter(s) in the backwash mode; and returning the at least one of the filter(s) to full filter mode.
 13. The method of claim 12 wherein the system condition is a preset time period.
 14. The method of claim 12 wherein the isolation and coupling between the plurality of filters, the fluid recovery line, the fluid supply line and the fluid backwash line is via a plurality of valve assemblies controlled by a control section.
 15. The method of claim 12 wherein upon completion of the backwash mode the at least one filter in backwash mode is refilled with water and the charge step and the purge step repeated at least once before returning to full filter mode.
 16. The method of claim 12 wherein upon completion of a backwash mode upon at least one of the filter(s), upon a next system condition the backwash mode is initiated with respect to a different group of at least one of the filter(s).
 17. The method of claim 14 wherein the charge time and the purge time are configurable at the control section.
 18. The method of claim 14 wherein the control section will continue to alternate the filters between the full filter mode and the backwash mode so long as the wash system is operating.
 19. The method of claim 14 wherein, when the wash system is not operating, the control section will initiate a backwash mode for the filters after a time period. 